Knee joint structure for walking dolls



April 5, 1960 D. COHN' 2,931,139

KNEE JOINT STRUCTURE FOR WALKING DOLLS Filed Feb. 2, 1955 3 Sheets-Sheet1 IN VEN TOR.

April 5, 1960 D. COHN 2,931,139

KNEE JOINT STRUCTURE FOR WALKING DOLLS Filed Feb. 2, 1955 3 Sheets-Sheet2 INVENTOR. D4 v/o Ca/vn/ April 5, 1960 D. COHN 2,931,139

KNEE JOINT STRUCTURE FOR WALKING DOLLS Filed Feb. 2, 1955 3 Sheets-Sheet3 INVENTOR. 04 W0 Co HIV 4rraevey United States Patent KNEE JOINTSTRUCTURE FOR WALKING DOLLS David Cohn, Brooklyn, N.Y., assignor toModel Plastics SCzorlproration, White Plains, N.Y., a corporation of NewApplication February 2, 1955, Serial No. 485,793 2 Claims. (Cl. 46173)This invention relates to a knee joint structure for walking type dolls.

In so-called walking dolls, the doll legs are interconnected so that ifthe doll is moved ahead on a supporting surface, alternating the motionfrom one leg to the other, the legs will be projected forwardly inalternation to simulate walking. In dolls of this type, it is desirablealso to so construct the legs that the members thereof, namely thethighs and the legs proper, may be articulated so as to relatively bendthe same between walking and sitting postures. However, for the walkingoperation it is essential that the'leg members (the thighs and the legsproper) be held in a linearly rigid walking posture, in resistanceagainst the relatively bending action and in resistance againstrelatively twisting or torsional action of the leg members.

The prime object of my present invention centers about the provision ofan improved knee joint structure for a walking type doll in which thereis made possible the manual articulation of the knee joint to relativelybend the leg members to and from a sitting posture, and in which the legand thigh members are held effectively in 'rigid walking posture inresistance against the relative bending action and in resistance againstthe relative twisting action of the leg and thigh members.

In such walking dolls constructed to also permit articulation of the legmembers at the knee, it is highly desirable to so construct the kneejoint that the joint is closed and the interior mechanism concealed fromview in all relative positions of the thigh member and leg member. It isa further prime object of the invention to devise an articulatable kneejoint for walking dolls so constructed that in both the sittingandwalking postures (and in all between positions) of the leg members,the knee joint is substantially closed, and in one form of the inventionit is completely closed, the interior mechanism of. the

joint being thereby substantially completely or fully concealed andhoused.

To the accomplishment of the foregoing objects and such other objects asmay hereinafter appear my invention relates to the knee joint structurefor walkiugdolls as sought to be defined in the appended claims and asdescribed in the following specification taken together with theaccompanying drawings, in which:

Fig. l is a view of a so-called walking type of doll to which thepresent invention is applied;

Fig. 2 is a vertical elevational view taken in medial cross-section ofthe leg members of such a walking doll and showing one form of the kneejoint structure embodying the principles of the present invention;

Fig. 3 is a front view taken in cross-section in the plane of the line3-3 of Fig. 2;

Fig. 4 is a view taken in cross-section along the broken lines 4-4 ofFig. 2;

Fig. 5 is a view similar to Fig. 2 but showing a modified form thereof;

Fig. 6 is a view of Fig. 5 taken in cross-section in the plane of theline 6-6 of Fig. 5;

2,931,139 Patented Apr. 5, 1960 Fig. 7 is a view of Fig. 5 taken incross-section in the plane of the line 7--7 of Fig. 5;

- Fig. 8 is a fragmentaryview of the essential parts shown in Fig. 5 andshowing these parts articulated to a sitting posture position; and

Fig. 9 is a view of Fig. 5 taken in cross-section along the broken lines9-9 of Fig. 5. 7

Referring now more in detail to the drawings and having reference firstto the form of the invention shown in Figs. 1 to 4 thereof, theprinciples of the invention are shown applied to a walking doll figure Dprovided with the Walking leg members comprising the upper leg membersor thighs 10 and the lower leg members (the legs proper) 12, Fig. 1showing the posture of the doll in the walking operation. The presentinvention is particularly directed, as aforesaid, to the knee jointstructure generally designated as 14 connecting. the leg members andthigh members of the doll. The knee joint itself is formed by the hollowthigh member 10 terminating in a socket 16 and by the hollow legmember'12 terminating in a ball 18 fitting the socket 16, the ball andsocket defining the knee joint proper. The leg members 10 and 12 may bemolded in the form thus depicted, using customary plastic materialswhich are molded into rigid shapes.

The mechanism for permitting'or enablingthe manual articulation of theknee joint 14 to relatively bend the thigh and leg members 10 and 12 toand from a sitting posture comprises a rigid link 20 preferably formedfrom sheet metal anchored at one end to the leg member 12 as by beingpivotally connected to a pin or rod 22 extending transversely throughthe ball 18 of the leg member 12, the said link extending upwardly andprotruding into the thigh member 10. The lower end of the link member isconfined within an angularly shaped groove or slit 24 formed in the legmember, the width of the groove being just sutficient to accommodate thethickness of the rigid link 20. A tensioning element such as the tensionspring 26 is anchored at one end 28 to the thigh member 10, as by beingattached to a cross-pin or rod 30 afiixed to the thigh member, and isanchored at the other end 32 to the upper end of the link 20.. The link20 and the tensioning spring 26 define the mechanism for holding the legmembers in jointed condition.

In the form of the invention shown in Figs. 1 to 4 the knee joint isalso'constructed and designed so that in the sitting and walkingpostures of the doll the knee joint is wholly closed and the interiorparts of the joint mechanism are fully concealed and housed. This isaccomplished by the following structure of the mechanism: the link 20 isprovided with ,an angular extension 34 formed with a linear slot "36,vthe anchoring element 38 for the end 3-2 of the tensioning spring beingarranged to be movable in said slot 36, thiscombined with theconstricting of the ball groove or slit 24 to an acute angle, as shownparticularly in Fig. 2 of the drawings. With this construction a fullbending movement (articulation at the knee) is permitted by the conjointmovement of the link 20 in the limited angular slit 24 of the ball and atoggleaction movement of the tensioning spring (the anchoring element38) in the slot 36' of the link extension 34. The full bendingarticulation is illustrated in Fig. 2 of the drawings, the walkingposture of the leg members being indicated in full lines and the sittingposture in dot-dash lines. In the full line or walking position the link20 is vertical and the anchoring element 38 is located in the upper endof the groove 36; and in the dot-dash or sitting position the 'link 20is moved to a slightly inclined position, the anchoring element 32 beingmoved to the lower end of the slot 36, the parts being held in bothpositions by a toggle action.

With the recited construction it will be observed par- ,and in 'allbetween positions.

,ence characters.

ticularly from Fig. 2. of the drawings that the movement of the link 20is accommodated in the groove or slit 24 of the ball 18 only over anacute angle, and that the ball 18 provides an exposable surface (seeparticularly the rear surface 40 of the ball) which is continuous anduninterrupted in both the sittingand walking postures of the legsThereby complete or full concealment and housing ofthe interiormechanism of the ball joint is achieved.

The means for positively holding the leg and thigh members in rigidwalking posture in resistance against the articulation of the members atthe knee comprises mating elements consisting of a protruding sector 42formed at the rear of the ball 18 on which normallyseats the rear edge.ofthe thigh socket. To move-the leg members to asitting posture the leg12 is slightly pulled relatively to the thigh member 10 sufiicient toeffect the release of the normal locking action between the protrudingsector 42 and the socket edge 44.

The means for normally holding the leg and thigh members in walkingposture in resistance against the relatively twisting or torsionalaction heretofore referred to is preferably rnade independent of themeans just described for resisitng the articulation of the members, andsuch means comprises the wall surfaces 46, 46 formedin the socket 16 andprotrusions or lugs 48, 48 on the ball 18, said lugs riding on said wallsurfaces during the articulation or bending action, the saidlugsactingjagainst the said wall surfaces to resist relative twistingaction between the leg member 12 and the thigh member 10.

In Figs. to 9 of the drawings I show a modification of the knee jointstructure embodying the principles of the present invention; and inthesefigures the parts which are similar to the parts shown in the formof the invention of Figs. 1 to 5 are designated by similar, but primed,refer- In this modification the ball18' of the knee joint is slittedfrom a medial plane of the leg member 12' at 50 over a larger angle thanthe acute angle of the slitted portion 24 of Figs. 1 to 5, and over anagle of substantially 90. However, this slitted portion is of a verynarrow width just sufiicient to accommodate the motion of thelink 52,such that'the ball 18' provides an exposable surface that is continuousthroughout except for the narrow groove defined by the slit 50(seeparticularly Fig.

9). The link 52 in this form of the invention is anchored to the legmember 12' by its lower pivotal connection to a pin orrod 54,andprotrudes intothe thigh member the tensioning spring 56 anchored byits upper end 58 to a crosspin 60 being connected at its lower end 62 tothe upper protruding end 64 of the rigid link. 1

In this structural form the mechanism for holding the leg and thighmembers inwalking posture in resistance against the relatively bendingaction or articulation of the leg memberscomprises, as before, aprotruding sector 42' with which is normally engaged the socket edgeportion 44'. The means for independentlynormally holding the leg andthigh members in walking'posture'in resistance against relativelytwisting action comprises a plate 66 fixedly attached to the thighmember 10', the same being provided with'a slot 68 through whichslidably and nonrotatably extends the upper part of the link 52. Toenable a yieldable action at the initiation of a bending orstraightening motion of the leg members it is preferred to extend theslot 68, a stop element in the form of a screw 70 being employed tolimit the transverse movement of the link 52 in one direction in theslot 68. With this construction the leg members are articulatablebetween the positions shown in Fig. 5 and in Fig. 8 of the drawings.

The knee joint structure of the invention especially designed forwalking type dolls, the manner of assembling the same and the mode ofoperating the same will, in the main, be fully apparent from theabove-detailed description thereof. It will be further apparent thatchanges may be made in the structure and the relation of the partswithout departing from the spirit of the invention defined in thefollowing claims.

I claim:

1. A ball and socket knee joint for a walking type doll comprising athigh member terminating in a socket, a leg member terminating in a ballfor fitting the socket, the ball ,and socket defining the knee joint,means for permitting themanual articulation of the knee joint torelatively bend said members to and from a sitting posture, said meanscomprising a link anchored to the leg member and protruding into thethigh member, a slotted plate fixed to the thigh member through whichthe link member extends in slidable but non-rotatable relation thereto,and a tensioning element fixedly anchored at one end to the thigh memberand movably anchored at the other end to the end of the link, the ballbeing slitted only at the rear .and only suificient to accommodate thelink during the ment permittingthe said manual articulation of the kneejoint to relatively bend said members to and from the said sittingposture.

Beebe H--. Feb. 5, 1957

